Edit - Retrocomputing Stack Exchange

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

30

I've been programming my whole life, most of it professionally - but I cut my teeth back when this was totally ambiguous to self-taught flunkies like myself. To this day I still transpose Mb for MB and don't even get me started on MiB... Bits and Bytes are measured in multiples of 1024 and anyone that says different is wrong wrong wrong! jk. :-P
– Geo...
Commented May 1, 2020 at 16:30
12

Except when you're seeing how fast the bits go down wires, and then it's k = 1,000, M = 1,000,000. (My first professional programming involved connecting computers to data communications links leased from the GPO)
– dave
Commented May 1, 2020 at 22:03
10

@Geo... I sympathize, but hard drive manufacturers, like 80s MIDI keyboard manufacturers, love to take any opportunity to be technically correct but deceptive about their numbers, so bytes in multiples of 1000 are too common to do anything but sigh and accommodate.
– ssokolow
Commented May 2, 2020 at 16:04
2

Being from the 80s, at the start of the decade Mb usually did mean megabit. It wasn't uncommon to measure memory in megabits. That was how you purchased memory: a byte-addressable machine of 16KB would have eight 16Kb chips. For larger computers not all computers were byte-addressable, and word sizes varied considerably between models, so if you wanted an idea of the size of memory, then expressing it in megabits was optimal. By the end of the decade the 8-bit byte was firmly established, byte-addressing was the norm apart from supercomputers, so one could then usefully say "megabytes".
– vk5tu
Commented May 3, 2020 at 13:06
1

@Geo... You are, of course, correct. Just that the prefix isn't k, but ki, and not M but Mi, and so on, and so forth... ;)
– I'm with Monica
Commented May 4, 2020 at 10:28

| Show 1 more comment

Correct minor typos or mistakes
Clarify meaning without changing it
Add related resources or links
Always respect the author’s intent
Don’t use edits to reply to the author

create code fences with backticks ` or tildes ~
```
like so
```
add language identifier to highlight code
```python
def function(foo):
print(foo)
```
put returns between paragraphs
for linebreak add 2 spaces at end
_italic_ or **bold**
quote by placing > at start of line
to make links (use https whenever possible)
<https://example.com>
[example](https://example.com)
<a href="https://example.com">example</a>

formatting help »
answering help »